The aim of this research is to identify the distributions of various lineage structures in the United States population in order to ascertain the degree to which they match the assertions about change made by gerontologists and demographers. We consider two types of lineage structure. Specifically, how prevalent are "bean pole" families? What is the distribution of the population into age-gapped, age-condensed, and truncated lineages? Most discussions of lineage structures focus on changes brought about by increased life expectancy and decreased fertility. Little research, however, has investigated how prevalent various structures are or how they affect intergenerational ties as they relate to support for old parents. The project will use Wave 1 (1987- 1988) and Wave 2 (1992-1994) of the National Survey of Families and Households, a panel study of a representative sample of the U.S. population aged 19 and older. Lineage structures will be categorized in two ways, first with respect to depth and size of generations to ascertain the prevalence of bean pole lineages in the population. Second, three-generations lineages will be categorized into 12 types that represent age-gapped, age-condensed, and truncated lineages as well as those which do not fall neatly into these three types. The relationship between the lineage type and race/ethnicity and social class will be described. Last, lineage type will be used in analysis as an independent variable to address the broad question of whether lineage type is associated with support for elderly parents. If there is evidence that lineage structure is a useful variable, recommendations will be made about data collection in future research.